DO AHEAD: Dough can be made 4 hours ahead. Press plastic wrap directly onto prepared dough and let stand at room temperature until ready to use. Preheat the oil to 170°C. Working in batches, scoop rounded teaspoonful of dough, then use second teaspoon to scrape dough into oil. Cook dough balls until puffed and golden brown on all sides, about 7 minutes. Using slotted spoon, transfer fritters to paper towels to drain. Toss zeppole in cinnamon sugar and serve warm.